As one type of indoor unit that constitutes a separate type air conditioner, there is known a wall-hung type indoor unit attached to an upper portion of a wall of a room. This wall-hung type indoor unit is provided with a receiving device comprising infrared receiving elements and the like for receiving a signal transmitted from a remote controller such that the indoor unit can be operated by the remote controller. The receiving device is usually provided to be directed in the forward direction of the indoor unit so as to be able to secure a reception distance when the indoor unit is operated by the remote controller, in view of that a room occupant will operate the indoor unit by using the remote controller from a diagonally lower position in front of the indoor unit.
Incidentally, as disclosed in Japanese Patent Application Publication No. H7-98129, there is also provided a wall-hung type indoor unit having a structure in which a front panel capable of opening and closing an air inlet provided is at the front side of a casing.